BowVector.cpp

/**
 * File: BowVector.cpp
 * Date: March 2011
 * Author: Dorian Galvez-Lopez
 * Description: bag of words vector
 * License: see the LICENSE.txt file
 *
 */

#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <cmath>

#include "BowVector.hpp"

namespace DBoW2 {
    
    // --------------------------------------------------------------------------
    
    BowVector::BowVector(void)
    {
    }
    
    // --------------------------------------------------------------------------
    
    BowVector::~BowVector(void)
    {
    }
    
    // --------------------------------------------------------------------------
    
    void BowVector::addWeight(WordId id, WordValue v)
    {
        BowVector::iterator vit = this->lower_bound(id);
        
        if(vit != this->end() && !(this->key_comp()(id, vit->first)))
        {
            vit->second += v;
        }
        else
        {
            this->insert(vit, BowVector::value_type(id, v));
        }
    }
    
    // --------------------------------------------------------------------------
    
    void BowVector::addIfNotExist(WordId id, WordValue v)
    {
        BowVector::iterator vit = this->lower_bound(id);
        
        if(vit == this->end() || (this->key_comp()(id, vit->first)))
        {
            this->insert(vit, BowVector::value_type(id, v));
        }
    }
    
    // --------------------------------------------------------------------------
    
    void BowVector::normalize(LNorm norm_type)
    {
        double norm = 0.0;
        BowVector::iterator it;
        
        if(norm_type == DBoW2::L1)
        {
            for(it = begin(); it != end(); ++it)
                norm += fabs(it->second);
        }
        else
        {
            for(it = begin(); it != end(); ++it)
                norm += it->second * it->second;
            norm = sqrt(norm);
        }
        
        if(norm > 0.0)
        {
            for(it = begin(); it != end(); ++it)
                it->second /= norm;
        }
    }
    
    // --------------------------------------------------------------------------
    
    std::ostream& operator<< (std::ostream &out, const BowVector &v)
    {
        BowVector::const_iterator vit;
        std::vector<unsigned int>::const_iterator iit;
        unsigned int i = 0;
        const unsigned int N = v.size();
        for(vit = v.begin(); vit != v.end(); ++vit, ++i)
        {
            out << "<" << vit->first << ", " << vit->second << ">";
            
            if(i < N-1) out << ", ";
        }
        return out;
    }
    
    // --------------------------------------------------------------------------
    
    void BowVector::saveM(const std::string &filename, size_t W) const
    {
        std::fstream f(filename.c_str(), std::ios::out);
        
        WordId last = 0;
        BowVector::const_iterator bit;
        for(bit = this->begin(); bit != this->end(); ++bit)
        {
            for(; last < bit->first; ++last)
            {
                f << "0 ";
            }
            f << bit->second << " ";
            
            last = bit->first + 1;
        }
        for(; last < (WordId)W; ++last)
            f << "0 ";
        
        f.close();
    }
    
    // --------------------------------------------------------------------------
    
} // namespace DBoW2